Villagers will claim a workbench that they can't pathfind to, including changing the specific work bench every time you relog, resulting in the majority of the villagers in a trading hall unable to refill their trades.

After upgrading my underground villager bunker, I have noticed that none of my villagers would restock on their trades even though they physically cannot pathfind to another workbench, and every time I log in it happens again, resulting in me having to break each workbench and slowly work my way through the bunker replacing each workbench as I find the villager who has claimed it.

Very annoying, especially if your trying to get a specific type of villager/trade.